FireAlpaca/ MediBang for drawing- layers, brushes,filters, saves as psd. MB has a library for importing backgriunds/ textures/ brushez. FA has animation features, no timelne yet
Mischief for drawing- infinite canvas, few brushez, if I remember corectly it has layer support
OpenToons for animation- never tried it
Sinfing for animation- has a bunch of tutorials on youtube among other places